Sugar beets are grown commercially for a wide variety of purposes including for sugar production. Leaf spot, caused by a fungus (Cercospora beticola) is one disease that often attacks sugar beet crops. The fungus is usually characterized by black, pycnidia containing, concentric circles. The fungus often eventually leads to necrosis of the leaf tissue. Failures of entire sugar beet crops have resulted directly from sugar beet leaf spot epidemics. There is a need for additional and/or more effective agents for protecting plants, including sugar beets, from damage caused by this pathogen.
Fungicides are compounds, of natural or synthetic origin, which act to protect plants against damage caused by fungi. Current methods of agriculture rely heavily on the use of fungicides. In fact, some crops cannot be grown usefully without the use of fungicides. The use of fungicides allows a grower to increase the yield and the quality of the crop and consequently, increase the value of the crop. In most situations, the increase in value of the crop is worth at least three times the cost of the use of the fungicide.
There are a number of fungicides used to control sugar beet leaf spot. These include both azoxtstrobin and difenconazole. Azoxtstrobin is the common name for methyl (αE)-2-[[6-(2-cyanophenoxy)-4-pyrimidinyl]oxy]-α-(methoxymethylene)benzeneacetate. Difenconazole is the common name for 1H-1,2,4-Triazole, 1-((2-(2-chloro-4-(4-chlorophenoxy)phenyl)-4-methyl-1,3-dioxolan-2-yl)methyl)-. Their fungicidal activity is described in The Pesticide Manual, Fourteenth Edition, 2006.
Unfortunately, in some cases known fungicides for leaf spot are not effective enough or may have other deleterious effects. Accordingly, it would be useful to discover new methods of controlling leaf spot in sugar beet crops.
Advantageously, a new method has been discovered. In one embodiment the present invention pertains to a new method for the control and prevention of sugar beet leaf spot caused by Cercospora beticola (CERCBE) in a sugar beet plant. The method comprises: applying a fungicidally effective amount of a compound of Formula I.

The effective amount is applied to at least one of the plant, an area adjacent to the plant, soil adapted to support growth of the plant, a root of the plant, foliage of the plant, and a seed adapted to produce the plant.